S&P downgrades U.S. credit rating

S&P downgrades U.S. credit rating: "

[Updated, 8:27 p.m. ET] The credit rating agency Standard & Poor’s announced Friday that it has downgraded the U.S. credit rating to AA+ from its top rank of AAA.

[Original post, 7:16 p.m. ET] The Standard & Poor’s rating agency served the Obama administration with notice Friday afternoon that it planned to downgrade the U.S. government’s AAA credit rating, an administration official told CNN.

But S&P has yet to make its ruling public, and the source told CNN the agency is reconsidering after the administration challenged S&P’s analysis of the government’s finances.

The source, a senior official involved in the discussions, said the agency was off by “trillions” in its economic model and was now working to revise its analysis.

S&P did not return repeated calls for comment.

The official described the talks as a “moving target” and said “it’s clear some people there still want to go forward” and downgrade U.S. debt.

Rumors swirled for most of the day Friday that S&P was preparing to make its move. But even several hours after the market close, official notice had yet to materialize.

Rating agencies — S&P, Moody’s and Fitch — analyze risk and give debt a “grade” that reflects the borrower’s ability to pay the underlying loans.

The safest bets are stamped AAA. That’s where U.S. debt has stood for years. Moody’s first assigned the United States a AAA rating in 1917.

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